1. Field of the Invention
The present invention relates to rotary engines including a rotor driving a shaft. In particular, the present invention relates to a rotary engine with multiple rotary tubular valves for introducing a power providing fluid into the engine and for outlet of exhausted fluid from multiple variable volume compartments formed by the rotor and engine housing and wherein the tubular valves are driven by fixed radial position rotatable gearing from the shaft.
2. Prior Art
In my U.S. Pat. No. 3,902,464, I described a rotary internal combustion engine having dual, eccentric cylindrically shaped rotors mounted on a shaft in closed housings such that the radius of maximum eccentricity from the shaft of one rotor was 180.degree. around the shaft from the other rotor. Sliding abutments were provided to form variable volume compartments in an Otto cycle engine. A special valving system with cams between the housings was described for inletting the combustible gas mixture into each compartment and for removing the exhaust gases. Conventional flat head or poppet valves were used. The engine provided an especially useful design; however, internal combustion rotary engines in general tend to be difficult and expensive to pollution control so as to meet environmental standards.
External combustion rotary engines are known to generate fewer pollutants. In these engines a fuel is burned in a furnace to provide a heated gas. The heated gas is used directly or the heat is exchanged to a second gas and the gas is provided under pressure to the engine to turn the rotor. Such engines can be steam-water (Rankin cycle) engines or constant temperature (Stirling cycle) engines. These engines and other engines are described in Scientific American Volume 239, No. 1 (July 1978) pages 39 to 49. In external combustion engines, the conventional poppet valves are less suitable since they do not provide effective sealing where there is a high pressure gas being supplied to (rather than in) the rotor compartments.
The use of rotary tubular inlet valves for engines is known, such as the valve described in U.S. Pat. No. 3,535,059 to Kalkbrenner. A curtain valve is used for the outlet of steam in the Kalkbrenner engine which also has only a single variable volume compartment per rotor. The engine is described as being suitable for miniaturization.
The particular problem solved herein was to develop an external combustion rotary engine which was simple and reliable and yet which would function as an external combustion engine to power multiple variable volume compartments. It was also necessary to develop an external combustion rotary engine which had a built-in compressor for pressurizing a gas and to provide heat regeneration wherein waste heat from the exhaust gas is transferred to the inlet gas.